How Gut Bacteria Affects Basically Every Aspect of Your Health

Here’s how scientists measure the will to live: Separate a young rat from his mother, throw him in a pool of water with no exit, and see how long it takes him to stop optimistically swimming in circles and start sadly treading water as he waits for the inevitable sink to the bottom. It’s a test to measure how long it takes to give up on life.

Don’t worry, the rat lives through it. We’re only bringing this up because in one such experiment in 2010, scientists found if the rat had been consuming probiotics, it was less likely to suffer from that anxiety and despair after being separated from its mother and tossed to its watery doom . Desbonnet,L., Garrett, L., Clarke, G., et al. Neuroscience, 2010 Nov 10;170(4):1179-88..

That's right: Probiotics—the so-called “good” bacteria that are often found in yogurt and help with digestion—might increase our will to live.

Bring on the Bacteria

One of the most exciting and revolutionary topics in health right now is also one of the least sexy: We’re talking about the bacteria that live in our digestive tracts—what science types often call the gut microbiome. Our bodies play host to trillions of these critters, and they make up a mini-ecosystem that helps us break down the food we eat and absorb its nutrients. At least, that’s all we thought the microbiome did.

So how can you manipulate your microbiome into helping you burn more fat? Diversity.

“You’ve got trillions of bacteria that help you digest food,” says Brad Pilon, a nutrition consultant and lead researcher on , a weight-loss system that cuts body fat by optimizing your gut bugs. “But when you don’t have enough kinds of bacteria in there, it can contribute to a lot of issues with your health, and there’s a real correlation with low gut diversity and obesity.”

Your Mind’s in the Gut

That brings us back to our water-logged rodent pal from the beginning and how probiotics can make rats (and even humans) less anxious: the so-called gut-brain axis.

The fact that the brain and belly are linked isn't surprising. (After all, indigestion is a fairly well-known .) But we’re now learning that connection is a two-way street: The mind can affect the gut, and the gut can affect the mind.

Here’s a good example: In 2011, British scientists gave probiotics to both rats and human subjects. After a month, they noted a significant decrease in both the rats’ anxiety-like symptoms and in the humans’ levels of anger, distress, hostility, and depression . Messaoud,i M., Lalonde, R., Violle, N, et al. British Journal of Nutrition, 2011 Mar;105(5):755-64.. More out of Oxford showed that supplements designed to boost the numbers of healthy gastrointestinal bacteria may improve anxiety levels by changing the way we process emotional information. The study participants were actually found to pay less attention to negative words and more attention to positive words after three weeks of supplementing . Schmidt, K., Cowen P.J., Harmer, C.J., et al. Psychopharmacology (Berl), 2014 Dec 3..

“Some people think this is a little out there," Pilon says. "But after all, we accept that your , and there’s evidence the . If you start viewing the microbiome as another organ, it makes a lot of sense.”

What You Can Do

Taking advantage of the many benefits of diverse, healthy gut bacteria isn't as easy as eating yogurt every single day—but it's not much harder, either. Follow these five steps.

2. Keep your weight down.

3. Be careful about antibiotics.

can be a doctor’s first response to conditions as common as , sinus infections, and . But these pills kill off massive amounts of both “good” and “bad” gut bacteria (“anti-biotic” is literally the opposite of “pro-biotic”). Worst of all, exposure to antibiotics at a young age may even influence whether a person will develop diabetes or Crohn’s disease later in life . Dicksved, J., Halfvarson, J., Rosenquist, M., et al. The ISME Journal, 2008 Jul;2(7):716-27.. de Goffau, M.C., Fuentes, S., van den Bogert, B., et al. Diabetologia, 2014 Aug;57(8):1569-77.. Try to explore alternatives whenever possible.

5. Eat lots of fermented foods.

This is super important. Foods like yogurt, kefir, sauerkraut, and kimchi are jam-packed with beneficial bacteria—just make sure the jars say they contain live cultures. If you’re not wild about these traditional sources, try making your own fermented food with this recipe, and play with the spices and veggies until you find something you like. If you can’t stand the slightly sour taste of fermented foods (or even if you can), are also a source of gut bugs.

The Takeaway

We weren’t kidding when we said practically every facet of your health is affected by an invisible alien ecosystem in your gut that you’ve probably never given much thought to. It’s kind of crazy, but it’s also important: At a time where there are rising rates of obesity and type 2 diabetes across America, we need to start thinking more about the microbiome and the role it can play in managing those health issues. Luckily, tending to your gut bugs doesn’t have to be complicated: Eat fermented foods, sleep a lot, fill up on fiber, and maintain a healthy weight. Your belly and your brain will thank you.